NEW YORK (CNN) -- U.S. safety officials have voluntarily recalled about 4.2 million Chinese-made Aqua Dots toys contaminated with a powerful "date rape" drug that has caused some children to vomit and lose consciousness upon ingesting the contents.

"Children who swallow the beads can become comatose, develop respiratory depression or have seizures," a CPSC statement warned.

"Anyone with Aqua Dots at home should throw them out," CPSC spokeswoman Julie Vallese said. The toy was named toy of the year in Australia and recently made Wal-Mart Store Inc's list of top 12 Christmas toys.

Wal-Mart on Thursday listed Aqua Dots on its Web site as "out of stock online" and had removed the toy from its top toy list as well.

The arts and craft beads, aimed at children four years and older, have been selling since April at major U.S. retail stores as "Aqua Dots" and in Australia under the name "Bindeez Beads."

Toronto-based toy distributor Spin Master Ltd. stopped shipping the Aqua Dots toys and asked retailers to pull them off their shelves, where they had sold for $17-$30. Watch what's known about the beads

Melbourne-based Moose Enterprise Pty. Ltd. recalled the Bindeez toys on Tuesday after three children in Australia swallowed large quantities of the beads and were hospitalized.

"I was so frightened because I thought she wasn't going to make it," Heather Lehane told CNN affiliate Network 7 of her 10-year-old daughter, Charlotte, who was among those children.

In the United States, the Washington-based safety commission said it has in recent days received two reports detailing the severe effects of the digested beads.

The CPSC said a boy nearly two years old "swallowed several dozen beads. He became dizzy and vomited several times before slipping into a comatose state for a period of time." The toddler was hospitalized and has since "fully recovered," the commission added.

In the second incident, a child vomited, fell into a coma and was hospitalized for five days. It was not immediately clear whether the child had made a full recovery.

The recall is the latest to target Chinese-made toys. Last month, U.S. government safety officials and retailers voluntarily recalled at least 69,000 Chinese-made toys over concerns of excessive amounts of lead paint, which can cause lead poisoning.